Stupid people always will do and will say stupid-s***.
FIP = ((13*HR)+(3*(BB+HBP))-(2*K))/IP + constant (3.20)
Real variables: HR, BB, HBP and IP
Every damn offensive event has a different value; While more bases you get, more value has the offensive event in question...
ERA doesn't tell much of a pitcher's true talent. Depend on where you play, the defense and luck.